1. Field of the Invention
The present invention relates to a container which stores liquids such as highly purified chemicals for semiconductors and ordinary chemical agents, and a plug for such a container.
2. Description of the Related Art
Generally, a semiconductor high pure chemical and an ordinary chemical agent are stored in containers which are resistable to such agents.
Formally, as shown in FIG. 16, two openings 1a are formed in this container 1, plugs 2 each of which has a plug section (not shown in the drawing) are positioned in these openings 1a. These plugs 2 function as lids which close the openings 1a, one is a plug 2a for connection to the liquid path, and the other one is a plug 2b for connection to the gas path, and a pipe 3 which extends to the vicinity of the bottom of the container 1 is connected to the liquid path plug 2a for connection to the liquid path.
Also, a cap is put on the plug sections of each plug 2 positioned in the openings 1a in this type of container 1, the through hole which is formed in the plug section is closed by this cap, and the liquid in this container is carried or stored in this state.
Consequently, when taking out the liquids stored in this container 1, firstly, after the caps which had been put on the plug sections of the plugs 2 which were positioned in the openings 1a are removed, sockets 5 connected with hoses 4 are connected to the plug sections of these plugs 2, and the liquid inside the container 1 is drawn out into the hose 4 by way of the pipe by a pump P.
Additionally, at this time, inert gas is fed into the container 1 from the hose 4 which is connected to the plug section of the plug 2b on the other side in such a way that the pressure inside of the container 1 is not negative. Also, it can be determined by the flow of gas on the gas drawing-side whether all the liquid inside the container 1 was fed out and whether the container 1 has become empty. Consequently, when a gas flow is detected, it is determined that the inside of the container 1 is empty, and this empty container 1 can be replaced by a new container 1 in which liquid is stored.
There are the cases in which the liquid inside the container 1 vaporizes as time goes by, so there is concern that the internal pressure increases during use. This occurs particularly when the liquid inside the container 1 is volatile.
Therefore, if the cap of the plug section of plug 2a for connection with the liquid path is detached when the internal pressure is high in this way, there is concern that the liquid will leak travel along the way of the pipe 3 and leak from the through hole of the plug section because of the internal pressure of the container 1.
For this reason, a sign is placed on the plug 2a on which the pipe 3 is provided indicating that the plug 2a is to be used for connection with the liquid path, and a sign is placed on the other plug 2b on which pipe 3 is not provided, indicating that the plug 2b is to be used for connection with the gas path. An operator detaches the cap put on the plug section of plug 2a for connection with liquid path, after identifying the signs on these plugs 2a and 2b and taking out the cap which was put on the plug section of plug 2a for connection with the gas path from the plug in order to lower the internal pressure of the container 1.
However, with the above container 1, the removal of the caps in turn has to be performed only according to the signs on the plugs 2a and 2b; therefore an improvement in safety is desired.
The present invention was made in light of the above situation, and an object of the present invention is to a provide a container and plugs for the container with greater safety such that liquid does not leak due to the internal pressure during use.
In order to achieve the above object, the container (1) according to a first aspect of present invention has a container body (10), at least one liquid path plug (11) and at least one gas path plug (12) which are attached to openings (10a) formed in the container body (10). The liquid path plug (11) has a lid section (14) attached to the opening (10a) in a watertight manner. A liquid path plug section (16b) having a through hole (16a) which communicates with an inner space of the container body and a pipe (17) which is connected to the liquid path plug section (16b). A liquid path plug section (16b) is provided in the container body, and a liquid path cap (22) is detachably attached to the liquid path plug section (16b) to block the through hole (16a). The gas path plug (12) has a lid section (14) attached to the opening (10a) in a watertight manner, and a gas path plug section (16c) having a through hole (16a) communicating with the inner space of the container body, and a gas path cap (22) which is detachably attached to the gas path plug section (16c) to block the through hole (16a). The gas path cap (22) has a disengaging section (35) which can be used to detach the liquid path cap (22) from the liquid path plug section.
In the container according to the first aspect, when drawing out the liquid inside the container by detaching the liquid path cap and the gas path cap which respectively close the through holes of the plug sections of the liquid path plug and the gas path plug fitted in the openings, because the liquid path cap is made detachable by means of the gas path cap which is detached from the plug section of the gas path plug. When detaching each cap in order to draw out the liquid inside the container, the detaching of the liquid path cap is always done after detaching the gas path cap. As a result, even if the internal pressure increases due to the vaporization of the liquid inside the container, when detaching the liquid path cap, the difference in the pressure between the inside and the outside of the container is nullified because the gas path cap of the gas path plug has already been detached. Therefore, problems such that the liquid inside the container passes along the pipe and leaks from the through hole of the plug can be securely eliminated.
More specifically, by performing above detaching steps, it is possible to quite easily detach the gas path cap and the liquid path cap from the gas path plug and the liquid path plug, connect the socket to which the hose is connected, and draw out the liquid inside the container.
In the container according to a second aspect of present invention, the gas path cap can be detached using the detaching fixture.
More specifically, when detaching the gas path cap which is put on the gas path plug section, because the detaching fixture is used, the step of opening the liquid path cap and the gas path cap is securely carried out; therefore safety can be further improved.
In the container according to a third aspect of present invention, the plug section is formed as a cylinder in which the through hole is formed in the center, the liquid path cap and the gas path cap are positioned covering the plug sections and the liquid path cap and the gas path cap are formed as cylinders having a bottom section such that the through hole of the plug section is closed.
More specifically, by putting respectively the liquid path cap which is formed as a cylinder which has a bottom section and the gas path cap on the plug section which is formed as a cylinder, it is possible to securely and easily seal the through holes of the plug sections of the container when carrying and storing.
With the container according to a third aspect, by respectively covering the plug section formed as a cylinder with the liquid path cap and the gas path cap which are cylinders with bottom sections, and by positioning the liquid path cap and the gas path cap on the plug sections, it is possible to securely and easily seal the through hole of the plug section of the container when carrying and storing.
In the container according to a fourth aspect of present invention, in a container as described in the third aspect has a male thread formed on the external surface of the plug section, a female thread which can engage the male thread of the plug section is formed on the internal surface on liquid path cap and the gas path cap, and by engaging the female thread to the male thread, the liquid path cap and the gas path cap are fitted into the plug section.
More specifically, by respectively twisting the liquid path cap side thread and gas path cap with respect to the plug sections, attachment and detachment of the liquid path cap and the gas path cap to and from the plug sections can be carried out easily.
In the container according to a fourth aspect, by turning respectively the liquid path cap and the gas path cap with respect to the plug sections, it is possible to quite easily attach the liquid path cap and the gas path cap to the plug sections and to detach the liquid path cap and the gas path cap from the plug sections.
In the container according to a fifth aspect of present invention, an engaging device which engage by means of convexo-concave interfitting is provided between the detaching fixture and the gas path cap, and between the gas path cap and the liquid path cap.
In this way, because the construction is such that the convexo-concave interfitting is provided between the detaching fixture and the gas path cap, and between the gas path cap and the liquid path cap, the operation of detaching the liquid path cap and the gas path cap can be easily performed.
In the container according to a sixth aspect of present invention, an engaging pin is provided on the detaching fixture so as to fit to an engaging hole section which is formed on the end surface of the gas path cap. An engaging protrusion section is formed on the gas path cap so as to fit to an engaging groove section formed on the end surface of the liquid path cap. An engaging device is constructed by respectively engaging the engaging pin with the engaging hole section, and the engaging hole section with the engaging groove section.
More specifically, by fitting the engaging pin of the detaching fixture into the engaging hole section of the gas path cap and by turning the engaging pin, it is possible to quite easily unscrew and detach the gas path cap using the detaching fixture, also by fitting the engaging protrusion section of the gas path cap into the engaged groove of the liquid path cap and by turning the engaging protrusion section, it is possible to quite easily unscrew and detach the liquid path cap using the gas path cap.
In the container according to a sixth aspect, by fitting the engaging pin of the detaching fixture into the engaging hole of the gas path cap and by turning the engaging pin, it is possible to unscrew the gas path cap using the detaching fixture and to detach the gas path cap quite easily, also by fitting the engaging protrusion section of the gas path cap into the engaging groove section of the liquid path cap and by turning the engaging protrusion section, it is possible to unscrew the liquid path cap using the gas path cap and detach the liquid path cap quite easily.
In the container according to a seventh aspect of present invention, a gas removal path which is closed by the cap which is fitted and communicates between the external surface and the bottom surface of the lid section is formed in the plug section of the liquid path plug, and when detaching the liquid path cap, the gas removal path is opened before the through hole.
In this way, even if in the worst case the internal pressure of the container increases when detaching the liquid path cap, when the liquid path cap is detached, the opening of the gas removal path formed in the plug section is opened and the inside of the container communicates with the outside of the container before the through hole of the plug section is opened, and problems that the liquid passes along the pipe and leaks from the through hole can be more securely avoided.
Accordingly, if an operator tries to detach the liquid path cap of the plug section of the liquid path plug of other container by using the gas path cap which is detached from the plug section of the gas path plug of the container, the leak of the liquid from the through hole of the plug section due to the internal pressure of the container can be securely prevented.
In the container according to the seventh aspect, even if the internal pressure of the container increases for whatever reason, when detaching the liquid path cap, the opening of the gas removal path formed in the plug section is opened, and the inside of the container communicates with the outside of the container before the through hole of the plug section is opened when detaching the liquid path cap, and problems such that liquid passes through the pipe and leaks from the through hole can be securely prevented.
Accordingly, even if an operator tries to detach the liquid path cap of the plug section of the liquid path plug of other container using the gas path cap detached from the plug section of the gas path plug of the container, it is possible to prevent securely the leakage of liquid from the through hole of the plug section due to the internal pressure of the container.
The plug which is used in the container described in an eighth aspect of present invention is characterized in that the lid section is attached to an opening of the container, the plug section has a through hole which is fixed to the lid section and connects the inside and the outside of the container, and a gas removal path is fixed to the lid section (14) and connects the inside and the outside of the container. A pipe connects the through hole which is provided in the plug section, a cap is fixed to the plug section, and closes the through hole and the gas removal path. The gas removal path is provided in the position such that the opening of the gas removal path is opened before the through hole is opened when detaching the cap.
More specifically, when opening the through hole of the plug section by detaching the cap, the gas removal path formed in the plug section is opened before the through hole is opened, and the inside of the container communicates with the outside of the container; therefore, the difference in the pressure is nullified even if the inside pressure of the container increases, and problems such that the liquid passes through the pipe and leaks from the through hole can be more securely avoided.
In the plug according to a ninth aspect of present invention, the plug section is formed as a cylinder in which the through hole is formed in the center, the gas removal path is opened on the external surface of the plug section, the cap is formed as a cylinder with a bottom section which covers the plug, a sealing material which seals the gap between the plug and the cap provided on the internal surface. When moving the cap which is fitted to the plug in the direction of the top of the plug in order to detach the cap, by moving the sealing material further forward the top of the plug section than the opening of the gas removal path, the gas removal path is opened before the through hole is opened.
More specifically, when moving the cap towards the top of the plug in order to detach the cap, because the sealing material provided on the internal surface of the cap moves to the farther side of the top of the plug than the opening part of the gas removal path, the gas removal path is opened before the through hole is opened, the difference in the pressure between the inside and the outside of the container is nullified, and problems such that the liquid passes through the pipe and leaks from the through hole can be more securely avoided.
In the plug according to a tenth aspect of present invention, the male thread is formed on the external surface of the plug on the plug section, the female thread which can be screwed with the male thread of the plug section is formed on the internal surface of the cap, and by screwing the male thread into the female thread, the cap is fixed to the plug section.
In this way, when detaching the cap which has been screwed into the plug section by unscrewing the cap, the sealing material provided in the internal surface of the cap moves towards the farther side of the top of the plug than the opening of the gas removal path, and the gas removal path is opened before the through hole is opened; therefore, the difference in the pressure between the inside and the outside of the container is nullified, and problems such that the liquid passes through the pipes and leaks from the through hole can be more securely avoided.
Also, by covering the plug section by the cap and by screwing the cap into the plug section, it is quite easily possible to put the cap on the plug section, close the through hole and the gas removal path, and perform the carrying the container and the storing the liquid in the container.
In the plug which is used in the container according to the tenth aspect, when unscrewing the cap which has been screwed onto the plug section and detaching the cap, the sealing material provided in the internal surface of the cap moves towards the farther side of the top of the plug section than the opening of the gas removal path, the gas removal path is opened before the through hole is opened, the difference in the pressure between the inside and the outside of the container is nullified, and problems such that the liquid passes through the pipe and leaks from the through hole can be securely prevented.
Also, by covering the plug section with the cap and by screwing the cap onto the plug section, it is possible to put the cap on the plug section, close the through hole and the gas removal path, carrying the container and store the liquid quite easily.